Had an issue this week on a pair of FAS8080s running 8.2.2P1 Cluster-Mode. During firmware upgrade for IOM6 module from version 0208 to 0209, I ran into ACP (Alternate Control Path) Connectivity Status showing “Partial Connectivity”.

I followed the recommended action plan:
1. Disable the ACP feature in ONTAP:
>options acp.enabled off
2. Reseat the IOM module with the unresponsive ACP processor.
3. Reenable the ACP feature:
>options acp.enabled on

That however, did not resolve the issue and we had to replace the module in order to correct. I did not disable ACP prior to replacement.